SB 

6/7 


ARHOW-GRASS  (Trigloohin  maritime) 
A  UBW  STOCK-POISOiaua  PLAUT 

By  C.E.  Fleming  &  Jf.F.  Peterson 
Unir.  of  Nevada  Bulletin  #98  -  Jan*  1920 


Agrio .  ~  ForeaU  y .  M  aiu  Lkxar 


PROPERTY   Oft 

"*\ 


AGRICULTURAL  EXPERlMElsff 

THE  UNIVERSITY  OF  NEVADA 


Bulletin  No.  98  January,  1920 


ARROW-GRASS 

A  New  Stock- Poisoning  Plant 

(TriglocJiin  maritima) 


By 

C.  E.  FLEMING  and  N.  F.  PETERSON 

Of  the  Department  of  Range  Management 
Assisted  by 

M.  R.  MILLER 

Of  the  Department  of  Chemistry 
and 

Dr.  L.  H.  WRIGHT  and  Dr.  R.  C.  LOUCK 

Of  the  Department  of  Veterinary  Science 


PUBLISHED  BY  THE  UNIVERSITY  OF  NEVADA 
RENO,  NEVADA 


I 

CARSON   CITY,  NEVADA 
STATE  PRINTING  OFFICE     :      :      :      JOE  FARNSWORTH.  SUPERINTENDENT 

1920 

I62 


3        J    3        »       >»       •  »»*') 

$0  : 


NEVADA  AGRICULTURAL  EXPERIMENT  STATION 


BOARD  OF  CONTROL 

Hon.  A.  E.CHENEY  (1921) 

Hon.B.F.  CURLEB  (1921) 

Hon.  WALTEB  E.PRATT  (1925)          .... 
Hon.  Mrs.  W.  H.  HOOD  (1927)  .... 

Hon.  MILES  E.  NORTH  (1929)    . 


Reno 
Elko 
Reno 
Reno 
Reno 


WALTER  E.  CLARK,  Ph.D. 
CAROLYN  BECKWITH 
CHARLES  H.  GORMAN 


SAMUEL  B.  DOTEN,  M.A.     . 
CHARLES  S.  KNIGHT,  B.S. 
F.  L.  BIXBY,  C.E. 

GEO.  HABDMAN,  M.S. 
CHARLES  E.  FLEMING,  B.S. A. 
N.  F.  PETERSON,  B.A.,  M.A. 
EDWARD  RECORDS,\T.M.D.  • 
STEPHEN  LOCKETT,V.M.D. 
LEWIS  H.  WRIGHT,  D.V.M. 
RUTH  MILLER.  B.A.  . 
M.  R.  MILLER,  B.S.     . 
HESTER  MAYOTTE 


OFFICERS 


.    President  of  University 

Secretary 

.        .  .        .        Comptroller 

STAFF 

Director  and  Entomologist 

Agronomist 

Bureau  of  Public  Roads,  Irrigation  Division. 

U.  S.  Dept.  of  Agriculture 
.        .        .        .        Assistant  Agronomist 

. Range  Management 

Assistant  in  Range  Management 

... Veterinarian 

Assistant  Veterinarian 

Assistant  Veterinarian 
Secretary  to  Veterinary  Department 

Chemist 

Librarian  and  Secretary  to  Director 


'-:  Library 


ACKNOWLEDGMENT 

The  Nevada  Agricultural  Experiment  Station  takes  pleasure  in 
thanking  A.  0.  Larson  of  Castle  Dale,  Utah,  for  suggestions  which  led 
to  the  study  of  the  poisonous  properties  of  Arrow-Grass,  and  to  Mr. 
G.  W.  Walts  of  Reno,  Nevada,  for  valuable  information  and  assistance. 


ANNOUNCEMENT 

In  July,  1918,  the  Nevada  Agricultural  Experiment  Station  pub- 
lished Bulletin  No.  95  entitled  "Range  Plants  Poisonous  to  Sheep  and 
Cattle  in  Nevada,"  by  C.  E.  Fleming,  head  of  the  Department  of  Range 
Management.  Hundreds  of  requests  for  copies  were  received  from 
stockmen  and  forest  rangers  in  Nevada  and  California.  The  Foreign 
Press  Bureau  of  the  Committee  on  Public  Information  requested  500 
copies  for  distribution  in  South  American  countries.  Although  the 
number  printed  was  unusually  large,  the  entire  edition  of  this  bulletin 
was  soon  exhausted  and  republication  has  become  desirable. 

Since  the  publication  of  Bulletin  No.  95  long  series  of  feeding  experi- 
ments with  poisonous  plants  have  been  made  at  the  Nevada  Station. 
Before  publishing  another  general  bulletin  on  the  subject  of  range 
plants  poisonous  to  sheep  and  cattle  it  seems  best  to  print  a  short 
series  of  bulletins  giving  the  results  of  feeding  tests  made  with  each 
poisonous  plant. 

We  plan  later  to  bring  together  the  results  of  all  the  new  experiments 
with  all  former  information  on  the  subject  in  another  illustrated  gen- 
eral bulletin  on  poisonous  plants. 

S.  B.  DOTEN, 

Director. 


481270 


Figure  1. 


Typical  plant  of  Arrow-Grass,  showing  cluster  of  leaves 
and  two  flower  stalks. 


Figure  2.    Arrow-Grass,  growing  among  other  plants  and  grasses. 


4-  6 


SUMMARY 

1.  Recent  experiments  conducted  by  the  Agricultural  Experiment 
Station  of  the  University  of  Nevada  show  that  under  certain  condi- 
tions the  grasslike  plant  commonly  known  as  Arrow-Grass  is  poisonous 
to  both  sheep  and  cattle. 

2.  Arrow-Grass  looks  -like  the  common  grasses ;    and  often  grows 
among  them  in  wet  soils  especially  where  the  ground  contains  alkali. 

3.  Figures  1,  2  and  3  of  this  bulletin  give  a  good  idea  of  the  general 
appearance  of  the  plant. 

4.  Arrow-grass  contains  an  unknown  substance,  which  is  sometimes 
broken  up  in  the  stomach  of  the  animal,  liberating  a  deadly  poison — 
hydrocyanic  ("prussic")  acid  gas. 

5.  Animals  fatally  poisoned  by  Arrow-Grass  breathe  very  rapidly  at 
first;    they  tremble,  breathe  through  the  mouth,  walk  around  stiffly, 
have  spasms  and  go  down  in  convulsions.     Later,  they  breathe  more 
slowly  and  with  increasing  difficulty,  spasms  continuing  at  intervals 
until  death,  which  occurs  in  from  half  an  hour  to  three  hours. 

6.  An  animal  must  eat  a  large  dose  at  one  time  in  order  to  be 
poisoned.    Small  doses  eaten  at  frequent  intervals  or  moderate  quanti- 
ties eaten  daily  have  no  harmful  effects. 

7.  Arrow-Grass  cut  and  dried  in  hay  is  far  more  dangerous  and 
deadly  than  the  green  plant. 

8.  When  the  body  of  an  animal  dead  of  Arrow-Grass  poisoning  is  cut 
up  there  is  little  indication  of  the  cause  of  death.     There  is  usually 
some  congestion  of  the  lungs  and  of  the  fourth  stomach,  but  neither 
condition  is  characteristic  of  this  plant  alone. 

9.  Because  of  the  nature  of  the  poison  and  because  death  follows 
poisoning  so  promptly,  there  is  little  hope  of  finding  methods  of  treat- 
ing and  curing  animals  seriously  poisoned  by  Arrow-Grass. 

10.  Places  where  Arrow-Grass  grows  very  thickly  should  be  fenced 
off.     Considerable  effort  should  be  made  to  prevent  Arrow-Grass  from 
being  cut,  dried  and  put  up  in  hay. 


ARROW=  GRASS 

A  New  Stock-Poisoning  Plant 

( Triglochin  maritima ) 


IN  THE  AUTUMN  OF  1918  we  were  informed  by  A.  0.  Larson  of 
Castle  Dale,  Utah,  that  cattle  had.  died  in  southern  Utah  from  eating 
a  plant  known  in  that  region  as  "goose-grass."  Fatal  poisoning  had 
been  caused  by  the  green  plants  in 
pastures  and  more  especially  by  the 
dried  plant  in  hay.  Specimens  sent 
by  Mr.  Larson  to  the  Nevada  Station 
were  identified  as  "arrow-grass"  or 
"sour-grass"  (Triglochin  maritima). 
Tire  small  amount  of  material  sent 
from  Utah  was  insufficient  to  produce 
any  symptoms  of  poisoning  in  sheep ; 
however,  as  this  plant  is  common  in 
wet  and  semialkaline  places  in  the 
vicinity  of  Reno,  experimental  feed- 
ings of  larger  amounts  were  begun  at 
once  and  continued  throughout  the 
spring  and  summer  of  1919.  These 
feeding  tests  showed  clearly  that 
under  certain  conditions  the  plant  is 
poisonous  to  both  sheep  and  .cattle. 
The  results  of  these  tests  are  given  in 
detail  in  this  bulletin. 

Common  Names. 

Triglochin  is  known  by  three  com- 
mon names  —  arrow-grass,  goose-grass, 
and  sour-grass.  Because  arrow-grass 
is  the  name  most  commonly  and  uni- 
versally used,  its  adoption  and  use  by 
stockmen  is  recommended. 

Description  of  Plant. 

This  poisonous  plant  belongs  to  a 
little  family  of  plants  known  as  the 
arrow-grass  f  amity.  It  grows  in 
bright-green  clumps  and  bunches,  so 
much  like  grass  that  it  is  hard  to  find 
in  the  midst  of  grasses  and  other 
plants  until  the  flower  heads  and  pods 
have  formed.  It  grows  in  scattered 
clumps  about  12  inches  wide,  or  in 
irregular  patches  which  may  be  from 
10  to  20  feet  or  more  across.  The  flat 
clumps  or  bunches  of  arrow- grass  grow  from  6  to  12  inches  high ;  and 
each  clump  of  leaves  bears  a  straight  slender  flower-stalk,  growing  to 


Figure  3.  In  grass  meadows  it 
is  hard  to  find  Arrow-Grass 
before  it  blooms. 


8  

a  height  of  from  12  to  30  inches.  The  flowers  and  seed-pods  form  a 
slender  cluster  from  6  to  12  inches  long.  The  flowers  themselves  are 
tiny  greenish  things,  and  are  soon  followed  by  the  oblong  three-sided 
seed-pods. 

The  leaf  of  arrow-grass  is  slender,  bright-green,  very  much  like- grass 
or  sedge.  Still  it  may  readily  be  told  from  grass  by  the  fact  that  it  is 

not  flat  like  a  grass-blade,  but  is  thick 
and  spongy,  flat  on  one  side  and  round 
on  the  other.    The  leaf  of  arrow-grass 
is  soft,  not  wiry  and  tough  like  that  of 
a  sedge.    The  leaves  are  attached  to  an 
underground  stem,  about  as  thick  as  a 
lead-pencil,  which  pushes  its  way  along 
beneath  the  surface,  sending  up  leaves 
and   sending   down   numerous   fibrous 
roots.     The  general  appearance  of  the 
plant  is  shown  in  Figures  1,  2  and  3. 
Figure  4.    Cross-section  of  Arrow-     A  flower  cluster  and  a  cluster  of  seed- 
Grass    leaf,    greatly    magnified.     p0(}s  are  shown  in  Figures  5  and  6. 
(X20).      The     leaf     of     Arrow- 
Grass  is  thick  and  spongy,  not     Distribution. 

°rdl"  Arrow-grass  is  widely  distributed 
over  the  northern  half  of  the  world. 
In  North  America  it  is  found  from  New  Jersey  to  California  and  from 
Labrador  to  Alaska.  On  the  sea  coast  it  grows  in  salt  marshes ;  inland 
it  may  be  found  in  wet  alkaline  soils  and  along  the  edges  of  sloughs, 
associated  with  grasses  and  sedges  and  other  plants  which  require 
much  water. 

Three  species  of  arrow-grass  occur  throughout  North  America  in  wet 
saline  or  semialkaline  soils.  At  least  two  of  them  occur  in  the  pas- 
tures and  meadows  in  Nevada,  but  Triglochin  maritime,  being  the 
larger  plant  and  the  most  common  is  probably  the  one  responsible  for 
most  of  the  stock  losses  that  occur  from  eating  this  plant.  It  is  not 
definitely  known  if  the  other  species  are  sufficiently  abundant  and 
poisonous  to  be  dangerous. 

Losses  Due  to  Arrow-Grass. 

But  little  is  known  concerning  the  extent  of  animal  losses  caused  by 
arrow-grass.  It  has  not  been  generally  considered  poisonous,  and  many 
losses  attributed  to  other  causes  may  have  been  due  to  this  plant. 
Dried  arrow-grass  mixed  with  hay  or  fed  free  from  mixture  is  readily 
eaten.  The  green  plant  does  not  seem  to  be  distasteful  to  animals,  and 
it  is  sometimes  eaten  greedily,  although  many  other  poisonous  plants, 
especially  those  containing  alkaloids,  are  so  bitter  that  stock  will  eat 
them  only  when  forced  to  do  so  by  extreme  hunger. 

Because  of  its  rather  pleasing  and  acceptable  taste  and  because  of  the 
fact  that  the  plant  often  grows  in  almost  pure  patches  from  a  few  feet 
to  rods  across  and  produces  a  large  quantity  of  forage,  it  would  seem 
easier  for  animals  either  on  pasture  or  on  hay  to  get  a  fatal  dose-  of 
arrow-grass  than  of  poisonous  plants  which  grow  scattered  here  and 
there  amid  other  foliage. 
The  Poisonous  Principle  of  Arrow-Grass. 

An  air-dried  sample  of  the  plant  (Triglochin  maritima)  used  in  the 
feeding  experiments  was  examined  in  the  Station  Laboratory  and  was 


found  to  possess  cyanogenetic  properties,  i.  e.,  would  yield  hydrocyanic 
acid  ("prussic"  acid)  upon  suitable  treatment. 

That  this  might  be  expected  was,  in  a  measure,  suggested  by  the 
symptoms  observed  in  the  feeding  experiments.  In  the  literature  it 
appears  that  Greshoff1  found  from  0.02%  to  0.6%  of  hydrocyanic  acid 


Figure  5.  Flowers  of 
Arrow-Grass  mag- 
nified (X2).  Flower 
is  small,  greenish, 
and  insignificant. 


Figure  6.  Seed-pods  of 
Arrow-Grass  mag- 
nified (X2). 


in  Triglochin  maritima.  Later  Blanksma2  in  working  with  the  same 
plant  found  hydrocyanic  acid  in  amounts  varying  from  0.056%  to 
0.184%,^  

'Greshoff,   M. :     A   New   Natural   Group   of  Plants   Containing   Hydrocyanic   Acid.      Pharm. 
Weekblad,  45.     1165-69,  1907. 

-Blanksma,   J.   J. :     Hydrocyanic  Acid  in   Sour-Grass  (Triglochin) .      Pharm.      Weekblad,    50. 

1295-1302. 


10 

In  the  plants  known  as  cyanogenetic  plants,  substances  have  been 
found  in  which  hydrocyanic  acid  is  in  combination  with  other  com- 
pounds. As  an  example  of  such  compounds  may  be  cited  amygdalin,  a 
compound,  which  will  yield  hydrocyanic  acid  and  benzaldehyde,  found 
in  the  bitter  almond.  Compounds  of  this  sort  may  be  made  to  give  up 
their  hydrocyanic  acid  by  the  action  of  suitable  reagents,  such  as  by  the 
action  of  acids  upon  amygdalin.  Another  method  of  breaking  off  the 
hydrocyanic  acid  is  by  the  action  of  certain  ferments.  Almost  invari- 
ably the  cyanogenetic  substance  is  found  to  be  accompanied  in  the  plant 
by  a  ferment  most  suitable  for  that  substance.  When  the  cells  of  the 
plant  are  broken  the  ferment  has  opportunity  to  act  upon  the  hydro- 
cyanic acid-holding  compound  and  the  acid  is  liberated. 

The  poisonous  properties  of  the  cyanogenetic  plants  may  be  reason- 
ably thought  to  be  due  to  hydrocyanic  acid  liberated  as  described  above. 
That  other  poisons  are  present  may  be  possible  and  has  been  suggested, 
but  laboratory  examination  has  failed  to  disclose  the  presence  of 
notable  amounts  of  other  poisonous  substances  such  as  alkaloids  or 
saponins. 

In  the  sample  submitted,  which  had  lost  79.2%  of  moisture  in  drying, 
there  was  found  0.264%  hydrocyanic  acid.  Calculated  to  the  original 
green  weight  of  the  plant,  this  is  equivalent  to  0.0549%  hydrocyanic 
acid  in  the  original  plant.  That  there  is  a  possibility  that  a  part  of  the 
hydrocyanic  acid  originally  present  in  .the  green  plant  was  lost  in 
drying,  has  been  shown  to  be  the  case  in  the  drying  of  sorghums.  This 
would  make  the  above  figure  lower  than  it  should  be  for  the  green 
plant.  Dowell3  showed  that  in  the  drying  of  sorghum  approximately 
three-fourths  of  the  acid  is  set  free. 

Laboratory  evidence  in  this  case  shows  that  we  have  been  dealing 
with  a  cyanogenetic  substance,  the  nature  of  which  will  form  the  sub- 
ject of  a  more  technical  paper  from  this  Station  in  the  future. 

Poisonous  plants  of  this  type  sometimes  appear  to  have  an  erratic 
action  both  in  feeding  experiments  and  also  when  animals  are  grazing 
at  will.  Apparently  the  grazing  of  sheep  and  cattle  upon  such  plants 
has  not  been  accompanied  with  fatal  results  in  every  case.  The  areas 
from  which  the  samples  used  in  these  experiments  were  obtained  have 
been  and  are  used  for  the  grazing  of  sheep  with  the  only  results  that 
at  times  lambs  succumb.  Cattle  have  been  fed  safely  upon  sorghums 
which  unquestionably  contained  hydrocyanic  acid  and  which  at  other 
times  and  under  different  conditions  of  feeding  caused  fatal  results. 
The  leaves  of  the  choke-cherry  contain  hydrocyanic-producing  sub- 
stances, but  poisoning  does  not  necessarily  accompany  natural  feeding, 
although  fatal  results  have  been  reported.  Linseed  cake  has  been  the 
subject  of  many  experiments,4  and  has  been  found  to  contain  lethal 
doses  of  hydrocyanic  acid  in  the  amounts  fed,  but  still  was  successfully 
used  in  feeding  and  fattening. 

In  explaining  such  a  state  of  affairs  it  is  necessary  to  consider  all  of 
the  possible  factors  which  contribute  to  the  action  of  these  compounds. 
Auld4  has  pointed  out  that  under  digestive  conditions  cyanogenesis  is 
likely  to  be  inhibited.  He  shows  that  the  presence  of  acids,  alkalies, 
salts,  cellulose  and  glucose  all  tend  to  prevent  the  liberation  of  the 

3Dowell,  C.  T. :    Cyanoprenesis  in  Androposron  Sorjfhum,     J.  Agr.  Res.  (1919)  16,  17,  175-81. 
<Auld,    S.    J.    M. :     CynnoRenesis    under    Dij?estive    Conditions.      Jour.    Agr.    Sci.  (1913)  51 
408-33. 


—  11  — 

poison,  and  that  in  the  cases  of  feeding  in  which  poisoning  occurs  it  is 
likely  that  there  is  some  element  which  interferes  with  the  inhibition 
which  would  normally  take  place.  The  possibility  of  the  formation  of 
hydrocyanic  acid  in  the  food  before  feeding  is  very  likely  in  cases  in 
which  the  feeding  stuff  is  manipulated  or  prepared  before  administra- 
tion. In  the  case  of  green  food,  only  the  rupturing  of  the  cells  is  suf- 
ficient to  produce  the  free  poison,  and  in  the  case  of  the  dry  material, 
which  is  generally  more  or  less  broken  up,  it  is  only  necessary  to  intro- 
duce moisture  to  produce  the  free  poison.  If  inhibition  can  be  due  to 
an  alkaline  medium,  the  normal  conditions  in  the  mouth  during  eating 
and  in  the  rumen  of  the  animal  would  have  a  protective  action  and 
would  tend  to  prevent  poisoning.  Anything  interfering  with  normal 
mastication  and  the  attendant  mixing  of  saliva  with  the  food  would 
evidently  interfere  with  the  inhibitory  process  and  end  with  disastrous 
results.  Auld  (loc.  cit.)  points  out  the  protective  effect  of  cellulose  and 
glucose,  and  that  these  carbohydrates  have  an  inhibitory  action  on  the 
evolution  of  hydrocyanic  acid  has  been  observed  by  other  investigators 
with  other  plant  materials.  In  fact,  it  has  been  recommended5  that 
glucose  be  used  as  an  antidote  in  cases  of<  poisoning  from  this  source. 
As  a  matter  of  fact,  it  is  probable  that  the  administration  of  glucose 
would  have  but  little  effect  if  done  after  the  symptoms  of  acute  poison- 
ing have  developed.  However,  if  a  suspicious  food  was  to  be  fed,  it 
might  be  mixed  with  a  glucose-containing  material  as  a  precautionary 
measure. 

Another  and  equally  important  factor  is  that  of  the  physical  con- 
dition of  the  animal  when  fed ;  the  state  of  its  health  and  whether  the 
food  in  question  is  taken  upon  a  partially  filled  or  empty. stomach.  It 
would  appear  in  the  case  of  sorghum,  for  example,  that  cows  turned 
into  sorghum  would  be  fatally  poisoned  if  nothing  had  been  eaten  for 
a  short  time  previously;  but  if  they  were  first  fed  and  then  allowed 
access  to  the  same  plants  no  poisoning  would  follow. 

The  Season  of  the  Year  when  Arrow-Grass  Is  Poisonous. 

Feedings  were  made  with  arrow-grass  cut  both  in  early  summer  and 
during  fall.  It  appeared  equally  poisonous  at  both  seasons.  There  is 
good  reason  for  believing  that  the  .plant  is  toxic  during  the  entire 
period  of  its  growth. 

The  Part  of  the  Plant  which  Is  Poisonous. 

The  greater  part  of  arrow-grass  consists  of  the  leaves,  the  flower 
stalk  making  only  a  small  portion  of  its  total  weight.  The  leaves  have 
been  conclusively  proven  to  be  poisonous.  We  have  not  found  out 
whether  the  flower  stalks  are  poisonous  because  they  are  more  or  less 
tough  and  unpalatable  and  make  up  only  a  minor  part  of  the  total 
weight  of  the  plant.  The  roots  are  so  firmly  held  down  by  their  fibrous 
growth  that  there  is  little  or  no  chance  of  their  being  eaten. 

The  following  tables  give  the  feeding  tests  which  were  made  with 
sheep  and  cattle  in  the  fall  of  1918  and  the  spring  and  summer  of  1919 ; 
all  the  animals  were  fed  the  fresh  green  leaves  except  a  single  sheep 
weighing  seventy  pounds  which  was  fed  three-fourths  of  a  pound  of 
the  green  fruits  without  results : 

•"'Peters,  A.  F.,  Slade,  H.  B.,  and  Avery,  Samuel:  Poisoning  of  Cattle  by  Common  Sorghum 
and  Kafir  Corn.  Nebraska  Station  Bulletin  No.  77. 


SHEEP-FEEDING  TESTS  WITH  GREEN  MATERIAL,  1918-1919 


Animal 
No. 

Weight 
of 
animal 

Date 

Time  fed 

Amount 
fed 

Time 
symptoms 
appeared 

Time  of 
death  or 
recovery 

Final  result 

42 

70  Ibs 

10-7  1918 

1  lb 

None 

40 

100  Ibs 

10-7  1918 

1  lb 

None 

39 

97  Ibs 

10-8-1918 

3*10  p   m 

l  '  Ibs 

3-25  p.  m. 

4:13  p.  m. 

..  Death 

42 

75  ibs 

10-10-1918 

2  Ibs 

-Slightly  sick 

10~15  1918 

11-40  a  m 

2  Ibs   ' 

12  -05  p  m 

1-40  p.m. 

Death 

46 

72  Ibs 

10-29  1918 

3  Ibs 

7R  lh<» 

11  7_1  qi  a 

9am 

•>  •  Jbg 

26 

75  Ibs 

4  12  1919 

1  lb 

29 

81  Ibs 

4  15-1919 

9'30  a  m 

1  lb 

26 

75  Ibs 

4~15  1919 

9*40  a  m 

li  Ibs 

73  Ibs 

6  3  1919 

11-40  a  m 

li  Ibs 

12'50  a  m 

1*15  p  m. 

Death 

46 

70  lh<» 

fi  ^  1Q1Q 

•  i  ]b 

6  4  1919 

10'50  a  m 

li  Ibs 

6  5  1919 

li  Ibs 

6-6-1919 

2  Ibs 

g_7  1919 

2\  Ibs 

None 

6-11-1919 
6  12  1919 

2  to  4  p.  m. 
9*20  a  m 

2i  Ibs. 
2;  Ibs 

4:30  p.  m. 
9-30  a  m 

7p.m. 
9'55  a  m. 

_-  Re'covery 
Death 

29 

80  Ibs 

6-11-1919 

9  to  10*20  a  m 

li  Ibs 

10-30  a  m. 

10:55  a.m. 

Death 

As  a  result  of  the  twenty  feeding  tests,  7  sheep  were  poisoned,  5  of 
which  died.  The  weight  of  green  material  required  to  make  a  sheep  sick 
or  to  kill  it  varied  from  1J  pounds  to  4J  pounds,  the  average  fatal  dose 
being  approximately  2.4  pounds.  Because  of  the  extremely  irregular 
way  in  which  plants  containing  hydrocyanic  acid  act  on  animals,  it 
would  be  difficult  to  state  accurately  just  how  much  of  the  plant  is 
required  to  kill  a  sheep  or  to  make  it  sick. 

However,  the  above  tests  demonstrate  conclusively  that  arrow-grass 
is  a  plant  containing  an  active  poison,  and,  although  the  amounts  neces- 
sary to  produce  sickness  or  death  may  seem  high,  in  reality  they  are 
not";  for  the  plant  is  made  up  of  a  rather  open  cellular  structure  con- 
taining a  high  percentage  of  water.  Further,  when  poisoning  does 
take  place  death  is  likely  to  follow;  this  is  shown  by  the  fact  that  of 
7  animals  poisoned  5  died.  Four  of  the  deaths  were  caused  by  2J 
pounds  or  less  of  green  material. 

A  series  of  feeding  tests  with  cattle  made  in  spring,  summer  and 
autumn  with  green  arrow-grass  failed  to  cause  poisoning.  The  tests 
are  summarized  in  the  table  at  the  top  of  page  13. 

Two  pounds  of  green  arrow-grass  had  no  effect  on  Steer  No.  735.  In 
October  this  animal  ate  an  average  of  15J  pounds  daily  for  7  days  or 
a  total  quantity  of  110J  pounds,  with  no  bad  effects.  The  material 
for  this  test  as  shown  in  the  table  was  collected  during  October.  The 
June  feeding  tests  also  resulted  negatively. 

These  results  cannot  be  taken  to  mean  that  fresh  green  arrow-grass 
is  not  poisonous  to  cattle;  for  we  must  constantly  keep  in  mind  the 
irregular  and  apparently  inconsistent  action  of  plants  containing 
hydrocyanic  acid.  There  is.  a  possibility  that  under  different  condi- 
tions of  feeding  and  at  another  time  the  feeding  of  the  same  quantity 
or  even  less  would  have  caused  poisoning.  Many  valuable  forage  plants 
in  the  sorghum  group  contain  hydrocyanic  acid;  and  yet  they  are 
ordinarily  fed  without  causing  losses.  However,  on  the  other  hand, 
ratner  serious  losses  in  cattle  have  been  caused  by  the  sorghums.  With 
arrow-grass,  the  same  erratic  action  may  be  expected.  This  test  would 
seem  to  indicate  that  pastures  where  arrow-grass  grows  are  ordinarily 
not  dangerous  to  cattle;  still,  there  is  always  a  possibility  that  they 
may  eat  just  the  right  amount  at  the  right  time  with  deadly  results. 


13 


CATTLE-FEEDING  TESTS  WITH  GREEN  LEAVES.  1918-1910 


Animal  No. 

Weight  of 
animal 

Date  fed 

Time  fed 

Amount  fed 

735                                                            „ 

530  Ibs. 

10-10-1918 

3  p.  m. 

2  Ibs. 

515  Ibs. 

10-10-1918 
10-12-1918 
10-15-1918 
10-22-1918 

10-23-1918 

10-26-1918 
10-27-1918 

4  p.  m. 
9  a.  m. 
9  a.  m. 
12  p.  m. 
1         10  a.  m.     » 
I          2  p.  m.     t 
2  p.  m. 
9  a.  m. 

9?  Ibs. 
11  Ibs. 
19  Ibs. 
20  Ibs. 

14  Ibs. 
23  Ibs. 

1 

137  Ibs. 

10-27-1918 
10-27-1918 
4-15-1919 

12m. 
4  p.  m. 
11:30  a.  m. 

10  Ibs. 
4  Ibs. 
1|  Ibs. 

7 

141  Ibs. 

6-4-1919 
6-5-1919 

6-6-1919 

6-7-1919 
6-8-1919 
6-10-1919 

6-10-1919 

10  a.  m. 
8:30  p.  m. 
1  p.  m. 
8  p.  m. 
8  a.  m. 
1  p.  m. 
3  p.  m. 
2  p.  m. 
1  p.  m. 
5:30  p.  m.    (. 

13i  Ibs. 
8i  Ibs. 

6i  Ibs. 

2i  Ibs. 
4  Ibs. 
8*  Ibs. 

8?  Ibs. 

8-11-1919 

10:30  p.  m. 
8:30  a.  m. 
5  p.  m.    1 

13£  Ibs. 

Feeding  Arrow-Grass  in  Hay. 

The  following  feeding  tests  were  made  with  sheep  and  cattle  to 
determine  the  effect  of  various  proportions  of  dry  arrow-grass  when 
put  up  in  hay  and  fed.  The  plant  material  for  these  feedings  was 
collected  in  1919  on  a  ranch  near  Reno.  One  lot  of  26J  pounds  of  fresh 
arrow-grass  was  collected  June  3,  4  and  5  and  air-dried  to  5J  pounds. 
Another  lot  of  38J  pounds  was  collected  on  August  9  on  the  same  ranch 
and  air-dried  to  9  pounds. 

SHEEP-FEEDING  TESTS  WITH  AIR-DRIED  ARROW-GRASS 


Animal  No. 

Weight 
of 
animal 

Date 
fed 

Time  fed 

Amount 
fed 

Time 
symptoms 
appeared 

Time  of 
death  or 
recovery 

Final  result 

60.  _. 

94  Ibs. 

8-5-1919 

4  p.  m 

8  ozs. 

4:50  p.  m. 

5:50  p.  m. 

Death 

37  .... 

83  Ibs. 

8-5-1919 

4-20  p.  m 

58  

101  Ibs. 

8-6-1919 

4:45  p.  m 
10  a.  m 

12  ozs. 

5:30  p.  m. 

Night 

Recovery 

53  

109  Ibs. 

8-6-1919 

11:30  a.  m 
10  a.  m 

4  ozs. 

5:15  p.  m. 

9:30  p.  m. 

Recovery 

11-30  a.  m 

4  ozs 

Negative 

54 

115  Ibs 

8-6-1919 

2'30  p  m 

3:30  p.  m 

5a  ozs. 

4  p.  m. 

4:35  p.  m. 

Death 

58 

100  Ibs 

8  7  1919 

1*30  p  m 

51--. 

96  Ibs. 

8-15-1919 

2:30  p.  m 
3-30  p   m 

4  ozs. 
1  oz 

3:20  p.  m.  ! 

7  p.  m. 

Recovery 
Negative 

53  „ 

105  Ibs 

8-15-1919 

1  oz 

Negative 

58-.. 

100  Ibs. 

8-16-1919 

8'50  a.  m 

3  ozs 

Negative 

51... 

96  Ibs. 

8-20-1919 

6-50  a  m 

1  oz 

Negative 

37 

87  Ibs 

8-20-1919 

2  oz 

61  —  

100  Ibs. 

8-20-1919 

7-20  a  m 

3  ozs 

8:80  a.  m 

10-15  a.  m. 

Death 

62 

82  Ibs 

8-20-1919 

7-30  a  m 

2i  ozs 

8*03  a  m 

9am 

Death 

TESTS  WITH  A  YEARLING  CALF 


1 

133  Ibs 

| 
8-8-1919      9  '30  a  m 

9-50  a  m 

10-20  a  m 

Deat 

Thirteen  feeding  tests  were  made  with  the  air-dried  material  fed  to 
,  six  of  which  tests  either  made  the  animal  very  sick  or  else  caused 
death.  These  tests  prove  conclusively  that  small  amounts  of  the  dried 
plant  are  highly  poisonous  to  sheep.  The  smallest  amount  which  was 
fatal  to  a  sheep  was  2J  ozs.,  the  average  fatal  dose  being  approximately 


14 


4.64  ozs.  Again  it  is  interesting  to  note  the  high  percentage  of  deaths 
among  the  poisoned  animals. 

The  one  feeding  test  made  with  the  yearling  calf  was  so  conclusive 
that  it  was  considered  unwise  to  sacrifice  any  more  cattle.  The  small 
amount  fed,  only  7  ozs.,  readily  produced  typical  poisoning  symptoms, 
and  its  action  was  so  characteristic  and  rapid  that  there  appeared  to 
b'e  no  immediate  need  of  other  tests  with  cattle. 

The  above  feedings  were  made  by  uniformly  mixing  with  alfalfa 
the  small  amounts  of  arrow-grass  tabulated.  Therefore,  these  tests 
show  very  clearly  that  there  is  considerable  danger  or  risk  of  loss  when 
arrow-grass  is  cut  and  put  up  with  hay  and  fed  to  live  stock. 

SHEEP-FEEDING  TESTS  WITH  SMALL  AMOUNTS  OF  ARROW-GRASS  IN  HAY 


Animal  No. 

Weight  of 
animal 

Date  fed 

Time  fed 

Amount  fed 

62 

821bs. 

August  9 

1:10  p.  m. 

1  oz. 

2:10  p.m. 

loz. 

3:10  p.  m. 

1  oz. 

4:20  p.  m. 

loz. 

Total 

4  ozs. 

51                                                             _.  

94  Ibs. 

August  8     !       9:50  a.  m. 

i  OZ. 

10:50  a.  m. 

Aoz. 

11:45  a.  m. 

A  oz. 

12:50  p.  m. 

oz. 

2:10  p.  m. 

oz. 

3:05  p.  m. 

oz. 

4:10  p.  m. 

oz. 

5:10  p.  m.                 •}  oz. 

6:10  p.  m.                 1  oz. 

Total 

5  oz. 

51                                                __  

97  Ibs. 

August  21         10:30  a.  m. 

oz. 

11:30  a.  m. 

oz. 

1:20  p.  m.                 1  oz. 

• 

2:30  p.  m.  |              *  oz. 

3:30  p.  m.  |              ;  oz. 

4:30  p.  m.  !               i  oz. 

7:00  a.  m.  !              1  oz. 

8:10  p.  m. 

oz. 

August  22 

9:00  p.  m. 
12:10  a.  m. 

oz. 
Loz. 

7:00  a.  m. 

1  oz. 

8:00  a.  m. 

loz. 

9:00  a.  m.                 '.  oz. 

10:00  a.  m. 

, 

oz. 

11:00  a.  m. 

oz. 

12:00  m. 

•i  oz. 

12:50  p.  m. 

*oz. 

1:45  p.m. 

oz. 

2:30  p.m. 

oz. 

3:15  p.  m. 

oz. 

4:00  p.  m. 

oz. 

4:45  p.  m. 

oz. 

. 

5:30  p.  m. 

oz. 

6:10  p.  m. 

oz. 

7:00  p.m. 

oz. 

7:45  p.  m. 

oz. 

August  23 

8:30  p.  m. 
6:40  a.  m. 

oz. 
oz. 

7:20  a.  m. 

oz. 

8:00  a.  m. 

oz. 

8:40  a.  m. 

oz. 

• 

9:20  a.  m. 

oz. 

10:00  a.  m. 

oz. 

10:40  a.  m. 

oz. 

12:00  m. 

oz. 

1:00  p.m. 

oz. 

1:30  p.m. 

oz. 

2:00  p.  m. 

oz. 

2:30  p.  m. 

oz. 

3:00  p.  m. 

los. 

N 

3:30  p.  m. 

[oc. 

4:00  p.  m. 

oz. 

4:30  p.  m. 

oz. 

4:50  p.  m. 

oz. 

5:10  p.  m. 

oz. 

15  

Feeding  of  Small  Amounts  at  Stated  Intervals  Mixed  with  Hay. 

The  object  of  this  series  of  feedings  was  to  determine  whether  small 
amounts  of  air-dried  arrow-grass  (the  total  of  which  if  fed  at  one  time 
would  cause  sickness  or  death)  would  be  harmful  when  fed  a  little  at 
a  time  at  various  intervals.  None  of  the  animals  were  affected  except 
No.  62,  which  showed  symptoms  of  poisoning  after  the  fourth  1-oz.  dose. 

The  above  feeding  tests  show  that  there  is  little  or  no  cumulative 
effect  of  small  doses  fed  at  short  intervals  or  over  a  long  period  of 
time.  Previous  to  these  tests  a  sheep  had  been  fed  4  ozs.  of  air-dried 
arrow-grass  which  readily  killed  the  animal.  However,  when  4  ozs.  of 
similar  material  was  fed  in  1-oz.  doses  to  a  sheep  at  hourly  intervals 
only  sickness  was  produced.  On  August  8  at  9 :  50  a.  m.  a  sheep  was 
given  ^  oz.  and  thereafter  -|-oz.  feedings  were  made  at  approximately 
hourly  intervals  until  6 :  10  p.  m.  when  1  oz.  was  fed.  In  all  between 
9 :  50  a.  m.  and  6 :  10  p.  in.  5  ozs.  had  been  fed  without  producing  any 
visible  symptoms  of  poisoning. 

On  August  21  at  10 :  30  a.  m.  a  prolonged  feeding  test  was  com- 
menced and  continued  until  5 :  10  p.  m.,  August  23,  during  which  time 
45  separate  feedings  w;ere  made  of  five  1-oz.  feedings  and  forty  ^-oz. 
feedings  or  a  total  of  25  ozs.  with  negative  results. 

From  these  feedings  it  appears  that  there  is  no  cumulative  action  of 
the  poisonous  principle  of  arrow-grass  when  eaten  in  small  amounts- 
of  less  than  1  oz.  at  short  intervals.  It  may  therefore  be  safely  con- 
cluded that  an  animal  may  eat  many  small  amounts  either  in  hay  or 
on  pasture  with  little  danger.  Thus,  if  small  quantities  of  the  dried 
material  are  uniformly  scattered  through  the  hay,  there  is  not  much  to 
worry  over,  so  far  as  the  health  of  the  animals  is  concerned.  On  the 
other  hand,  if  there  is  any  considerable  quantity  in  the  hay,  fatal 
results  may  be  expected  especially  if  fine,  broken  material  collects  in 
the  bottom  of  the  feed  racks.  Dry  arrow-grass  is  very  brittle,  easily 
broken,  and  may  very  readily  sift  to  the  bottom  along  with  seeds,  chaff, 
and  other  material.  If  this  takes  place,  then  there  is  a  possibility  of 
fatal  poisoning,  even  though  there  is  only  a  small  amount  of  the  plant 
in  the  hay. 

DETAILED  DESCRIPTION  OF  TYPICAL  CASES  OF  ANIMAL  POISONING 
Case  No.  1— No.  39. 

f 

A  sheep  weighing  97  pounds  was  fed  4^  pounds  of  green  arrow-grass 
leaves  at  3 :  10  p.  m.  October  8,  1918.  The  animal  appeared  sick  at 
3  :  25  p.  m.  within  fifteen  minutes  after  feeding.  Muscular  spasms  com- 
menced at  3:30  p.  m. ;  hindlegs  pulled  up  under  body;  frequent 
champing  of  jaws,  breathing  hard  and  audible.  At  3 :  40  the  sheep  was 
breathing  through  the  mouth  which  was  held  wide  open  with  the 
tongue  hanging  out ;  temperature,  102  ;  respiration,  30.  At  3 :  50  p.  m. 
spasms  continued ;  3  :  55  p.  m.,  respiration,  21 ;  at  3 :  58  p.  m.,  severe 
spasms  commenced  and  breathing  practically  stopped ;  at  4 :  03  p.  m., 
respiration  12,  with  long  intervals  between  breaths.  Expulsion  of 
breath  forcible  and  plainly  audible ;  at  4 :  12  p.  m.  respiration  had 
fallen  to  8.  Death  occurred  at  4 :  13  p.  m. 

Autopsy  showed  the  jejunum  severely  congested ;  spleen  dark  and 
mushy;  kidneys  congested ;  lungs  slightly  congested ;  other  organs  all 
appeared  normal. 


16 


Case  No.  2— No.  42. 

A  ewe  weighing  75  pounds  was  fed  2  pounds  of  green  arrow-grass 
leaves  at  11 : 40  a.  m. ;  at  12 : 05  p.  m.  she  was  walking  with  a  stiff 
peculiar  gait  the  hindlegs  far  apart  and  held  back.  Soon  muscular 
twitchings  commenced.  At  12:25  p.  m.  the  respiration  was  25.  At 
1 2 :  30  she  fell  down,  displaying  spasms  with  a  peculiarly  regular  up- 
and-down  movement  of  the  head.  Spasms  occurred  at  short  intervals 
until  a  little  before  death.  At  1 :  28  p.  m.  the  respiration  was  19.  At 
1 :  37  p.  m.  the  mouth  was  held  open  with  the  tongue  out  and  breathing 
had  almost  ceased.  Death  occurred  at  1  :.40  p.  m. 

Autopsy  showed  moderately  congested  abomasum,  spleen  dark  and 
mushy,  small  intestine  congested,  lungs  slightly  congested;  all  other 
organs  apparently  normal. 

Case  No.  3— No.  26. 

A  yearling  wether  weighing  73  pounds  was  fed  1^  pounds  of  green 
arrow-grass  leaves  at  11 :  40  a.  m.  At  12 :  50  p.  m.  he  was  down  on  his 


Figure  7.    Sheep  in  early  stages  of  Arrow-Grass  poisoning. 

belly  with  legs  stretched  out,  mouth  open;  very  audible  breathing 
through  mouth,  and  distinct  twitching  movements  of  head  and  rolling 
of  eyes.  At  1  p.  m.,  respiration  16,  temperature  103.2.  Had  a  series 
of  spasms  at  regular  short  intervals  until  death,  which  occurred  at 
1:  15  p.  m. 

Autopsy  showed  fourth  stomach  slightly  reddened,  small  hemor- 
rhages on  heart ;  spleen  darkened ;  all  other  organs  apparently  normal. 

Case  No.  4— No.  46. 

A  ewe  weighing  70  pounds  was  fed  2J  pounds  of  green  leaves  of 
arrow-grass  between  2  p.  m.  and  4  p.  m.  She  commenced  to  feel  dis- 
tressed and  acted  unnatural  almost  as  soon  as  the  feeding  was  finished, 
standing  with  head  down,  appearing  very  dull  and  caring  little  to 
move  about.  This  state  of  inactivity  was  maintained  until  5 :  45  p.  m. 
when  she  commenced  to  brighten  up,  and  at  7  p.  m.  appeared  quite 
normal,  for  she  was  eating  a  little  hay. 


Case  No.  5— No.  46. 

The  same  sheep  as  in  Case  No.  4  was  again  fed  the  next  day  2J 
pounds  at  9  :  20  a.  m.  and  was  very  sick  by  9  :  30  a.  m.  She  was  breath- 
ing through  the  open  mouth,  with  frequent  twitching  movements  of 
the  muscles  of  the  neck,  wrinkling  movements  of  the  lips  and  a  chewing 
movement  of  the  jaws.  At  9 : 45  a.  m.  she  was  down  on  her  side  with 
spasms  most  of  the  time  until  9  :  50  a.  m.,  when  she  began  to  regurgitate 


Figure  8.     Sheep  down  in  convulsions,  Arrow-Grass  poisoning. 


Figure  9.    Sheep  dying  from  Arrow-Grass  poisoning. 

food  which  passed  out  both  through  the  mouth  and  nostrils.     Death 
occurred  at  9 :  55  a.  m.,  thirty-five  minutes  after  she  was  fed. 

Autopsy  (by  Dr.  R.  C.  Louck)  :  Slight  congestion  of  fourth  stomach, 
large  intestine  congested ;  small  hemorrhages*  on  ventricles ;  all  other 
organs  apparently  normal. 

Case  No.  6— No.  29. 

A  yearling  lamb  weighing  80  pounds  was  fed  three-fourths  of  a 


18  

pound  of  green  material  between  9  a.  m.  and  10 :  20  a.  in.  He  was  sick 
at  10 :  30  a.  m.  ten  minutes  afterwards.  Breathing  through  the  mouth 
was  very  audible ;  and  the  animal  was  soon  down  on  its  side.  The 
respiration  was  50,  temperature  101.4.  He  lay  on  his  side  with  dif- 
ficult breathing  and  series  of  spasms  at  frequent  intervals  until  shortly 
before  death,  which  occurred  at  10 :  55  a.  m.,  thirty-five  minutes  after 
feeding. 

The  autopsy  showed  small  hemorrhages  of  the  heart;  all  other 
organs  appeared  normal.  Because  of  regurgitation  shortly  before 
death,  the  lungs  contained  food  material. 

Case  No.  7— No.  60. 

A  ewe  weighing  94  pounds  was  fed  8  oz.  of  the  dry  leaves  at  4  p.  m. 
At  4 :  50  p.  m.  she  was  down  and  unable  to  rise.  Peculiar  jerky  move- 
ments of  the  head  took  place.  At  5  p.  m.  she  began  having  a  series  of 
convulsive  spasms  at  intervals  of  four  or  five  minutes  until  death, 
which  occurred  at  5 :  50  p.  m.  Just  before  death  she  vomited  a  little. 

Autopsy  showed  slight  inflammation  of  colon;  severe  congestion  of 
both  lungs ;  slight  hemorrhages  in  the  endocardium  of  the  ventricles. 

Case  No.  8— No.  37. 

A  ewe  weighing  83  pounds  was  fed  12  ozs.  of  the  dry  leaves  between 
4 :  20  p.  m.  and  4;  45  p.  m.  At  5 :  30  p.  m.  she  was  dull  and  could 
hardly  be  induced*  to  get  up.  Slight  jerky  movements  of  the  muscles 
of  the  head  and  neck  took  place,  becoming  more  pronounced  until  7 :  20 
p.  m.  When  next  observed,  at  9 :  30  p.  m.,  she  was  much  better,  being 
up  and  walking  about,  but  still  very  much  indisposed.  Next  morning  at 
8  a.  m.  she  appeared  to  have  fully  recovered. 

Case  No.  9 — No.  58. 

A  ewe  weighing  101  pounds  was  fed  4  ozs.  of  the  dry  leaves  between 
10  and  11 :  30  a.  m.  At  5 :  15  p.  m.  she  was  breathing  rapidly,  the 
respiration  being  150  per  minute.  This  condition  lasted  until  7  p.  m. 
No  other  symptoms  were  observed.  Next  morning  she  was  eating  a 
little  hay ;  at  9 :  30  a.  m.  the  following  day  she  appeared  to  have  fully 
recovered. 

Case  No.  10— No.  54. 

A  ewe  weighing  115  pounds  was  fed  5 J  ozs.  between  2 :  30  p.  m.  and 
3 :  30  p.  m.  At  4  p.  m.  she  was  sick,  breathing  through  the  mouth ; 
respiration,  104 ;  temperature,  103.6.  While  standing,  frequent  jerky 
muscular  movements  of  the  whole  body  took  place.  At  4 :  12  p.  m.  she 
was  down  with  head  and  legs  moving  almost  constantly,  except  during 
spasms  when  the  legs  were  stretched  out  and  the  head  and  neck  drawn 
back.  The  animal  died  at  4 :  35  p.  m. 

Autopsy  showed  considerable  congestion  in  rumen  and  fourth 
stomach ;  spleen  darkened  and  mushy ;  kidneys  congested ;  abdominal 
lymph  glands  congested  ;  lungs  moderately  congested. 

Case  No.  11— No.  58. 

A  ewe  weighing  100  pounds  was  fed  2  ozs.  of  the  dry  leaves  at  1 :  30 
p.  m.  and  2  ozs.  more  at  2  :  30  p.  m.  At  3  :  20  she  was  sick ;  respiration, 
70 ;  breathing  deep  and  audible ;  trembling  of  the  muscles,  especially 
those  of  the  legs.  At  3 :  40  she  was  down ;  respiration  30 ;  breathing 
hard  and  very  audibly  through  the  mouth.  She  remained  down  with 


19 


head  flat  on  the  ground  until  after  5 :  10  p.  in.  At  5 :  50  p.  m.  she  was 
up  and  able  to  walk,  but  still  quite  weak.  At  7  p.  m.  she  appeared  to 
have  fully  recovered. 

Case  No.  12— No.  61. 

A  ewe  weighing  100  pounds  was  fed  3  ozs.  of  air-dried  leaves  at  7 :  20 
a.  m.  At  8 :  30  a.  m.  she  was  sick.  Down  on  side  with  spasms  at  9 :  30 
a.  m. ;  respiration,  44;  temperature,  103.6.  Breathing  was  mainly 
through  the  mouth.  At  10  a.  m.  she  was  lying  quietly  on  her  side, 
breathing  hard  and  audibly.  Died  at  10 :  15  a.  m. 

Autopsy  showed  considerable  congestion  of  lungs  and  a  few  small 
hemorrhages  of  the  heart.  Other  organs  presented  no  gross  lesions. 

Case  No.  13— No.  62. 

A  ewe  weighing  82  pounds  was  fed  2J  ozs.  of  dry  arrow-grass  leaves 
at  7 :  30  a.  m.  Sick  at  8 :  03  a.  m.,  having  a  peculiar  twitching  of  the 
muscles.  Down  on  one  side  at  8 :  30  a.  m.  Frequent  spasms  occurred. 


Figure.  10.  Calf  dying  in  convulsions  from  Arrow-Grass  poisoning. 

Respiration,  65 ;    temperature,  104.2.     At  8 :  45  a.  m.  respiration  had 
fallen  to  28.    Death  took  place  at  9  a.  m. 

Autopsy  showed  congestion  of  lungs  and  of  the  fourth  stomach. 
Other  organs  appeared  normal. 

Case  No.  11— No.  62. 

A  ewe  weighing  82  pounds  was  fed  4  ozs.  of  dry  leaves,  an  ounce  at 
a  time  hourly  in  order  to  find  out  if  the  poison  would  be  eliminated 
fast  enough  so  that  poisoning  symptoms  would  not  develop.  The  last 
feeding  was  at  4 :  20  p.  m.  and  at  5  p.  m.  she  was  sick.  The  first  notice- 
able symptom  was  a  trembling  of  the  muscles  of  the  legs ;  respiration, 
70.  At  5 :  02  p.  m.  she  was  down,  breathing  through  the  mouth.  She 
remained  in  this  condition  until  after  6 :  30  p.  in.  At  7 :  30  p.  m.  she 
was  up.  walking  around,  but  soon  fell  down  again.  She  was  soon  on 
her  feet  again,  but  at  7 :  40  she  had  another  spasm  and  fell  down.  At 
10 :  30  p.  m.  she  was  up  and  able  to  walk  around,  her  gait  was  very 
unsteady;  the  next  morning  at  7:  30  a.  m.  she  appeared  to  have  fully 
recovered. 


20  

Case  No.  15— No.  1. 

A  small  yearling  calf  was  fed  8  ozs.,  of  which  almost  1  oz.  was  left 
uneaten  at  9 :  30  a.  m.  At  9 :  50  a.  m.  he  was  sick.  Most  of  the  time 
he  lay  on  his  side  and  at  frequent  intervals  he  had  spasms  when  his 
head  would  be  pulled  back  and  legs  stretched  out.  At  10 : 15  the  res- 
piration was  10 ;  and  he  appeared  to  be  dying.  He  died  at  10 :  20  a.  m. 

The  autopsy  revealed  no  lesions. 

Symptoms  of  Poisoning. 

The  first  symptom  noted  was  abnormal  breathing,  usually  very 
rapid,  often  as  high  as  150  per  minute,  in  sheep.  In  other  cases  it  was 
slow  and  deep.  As  symptoms  of  poisoning  developed,  the  animal 
breathed  quite  freely  through  the  mouth,  often  with  the  tongue  hang- 
ing, out.  This  abnormal  breathing  was  often  accompanied  by  trem- 
bling or  jerking  movements  of  the  muscles.  In  severe  cases  these 
jerking  movements  would  develop  into  spasms  or  convulsions.  After 
these  started  the  animal  would  lie  on  its  side  panting  through  the  wide- 
open  mouth.  From  the  time  the  animal  ^rent  down  until  partial 
recovery  or  death  there  would  be  a  series  of  convulsions  at  short  inter- 
vals. Several  of  the  animals  vomited  just  before  death,  drawing  part  of 
the  regurgitated  material  into  the  lungs,  which  may  have  hastened 
death. 

Autopsy  Findings. 

The  autopsy  findings  are  few  and  not  characteristic  in  any  way, 
with  the  possible  exception  of  congestion  of  the  lungs.  Fifty  per  cent 
of  the  cases  showed  endocardial  or  epicardial  hemorrhages  and  forty 
per  cent  a  spleen  that  was  dark  and  mushy.  In  general,  the  blood  was 
darker  than  normal  and  formed  a  clot  that  was  rather  soft.  The 
moderate  congestion  observed  in  the  intestinal  tract  is  of  little  signifi- 
cance, and,  because  of  the  lack  of  uniformity  of  the  location  of  the 
lesion,  might  be  due  to  other  causes.  No  odor  of  cyanide  was  noted  in 
any  of  the  cases ;  but  all  the  autopsies  were  made  in  the  open. 

If  these  deaths  were  due  to  cyanide  poisoning  as  indicated  by  the 
symptoms  and  chemical  findings,  the  autopsy  findings  would  probably 
be  negligible.  Various  writers  on  toxicology  consider  the  post-mortem 
changes  in  cyanide  poisoning  as  of  little  aid  in  diagnosis.  Nunn 
(Veterinary  Toxicology,  1907,  p.  130)  states:  "The  post-mortem 
appearances  are  nothing  characteristic,  excepting  the  pervading  smell 
of  almonds  from  the  intestines  and  in  a  lesser  degree  from  the  whole 
body."  Friedberger  and  Frohner  (Veterinary  Pathology,  Vol.  I, 
Translation  by  Hayes,  Sixth  Edition  1908,  p.  236)  say:  "Autopsy 
shows  bright-red  blood  in  acute  cases,  brown  when  chronic;  smell  of 
bitter  almonds ;  signs  of  asphyxia." 

Feeding  Conditions  under  which  Poisoning  by  Arrow-Grass  Is  Likely  to  Occur. 

Few  cases  of  natural  poisoning  have  been  observed.  In  one  instance 
an  owner,  of  live  stock  stated  that  he  had  had  a  number  of  cows  in 
corral  on  dry  feed  for  some  time.  On  releasing  them  they  went 
directly  to  a  patch  of  arrow-grass  which  they  ate  greedily.  There  was 
very  little  grass  or  sedge  in  the  patch.  The  poisonous  material  was 
therefore  but  little  diluted,  and  the  death  of  several  animals  soon  fol- 
lowed. The  same  stockman  reported  that  he  was  very  likely  to  lose 
animals  when  they  were  fed  from  a  stack  of  wild-grass  hay  cut  on 


21  

meadows  containing  large  quantities  of  arrow-grass.  A  sheep  owner 
reported  the  death  of  lambs  when  they  fed  late  in  the  spring  on 
meadows  where  arrow-grass  was  abundant.  From  the  statement  it 
appeared  probable  that  death  was  due  to  this  plant. 

There  seems  some  reason  to  believe  that  the  plant  might  cause  death 
in  animals  which  had  been  on  dry  feed  so  long  that  they  would  fill  up 
on  almost  anything  green.  There  appears  to  be  greater  danger  when 
the  plant  is  fed  dry  in  hay ;  the  dose  required  to  kill  is  then  far  smaller, 
and  there  is  greater  probability  that  a  fatal  quantity  will  be  eaten. 

Cure  of  Animals  Poisoned  with  Arrow-Grass. 

No  experiments  were  made  to  determine  whether  it  would  be  possible 
to  cure  a  poisoned  animal.  Apparently  there  is  little  hope  or  prospect 
of  success,  because  a  dose  large  enough  to  cause  illness  is  likely  to  cause 
death,  and  because  the  interval  between  the  time  when  the  first  symp- 
toms appear  and  the  fatal  result  is  too  short  to  permit  of  treatment. 

Prevention  of  Poisoning. 

With  arrow-grass  as  with  other  poisonous  plants  it  appears  that  not 
much  can  be  hoped  for  in  the  cure  of  animals  already  poisoned,  but 
that  a  good  deal  can  be  done  to  prevent  poisoning.  Wet  meadows, 
where  arrow-grass  is  very  common,  should  not  be  cut  for  hay.  How- 
ever, where  the  plant  is  distributed  in  small  clumps  rather  uniformly 
and  is  not  very  abundant  there  is  little  danger.  The  largest  clumps 
should  not  be  cut,  or,  if  cut,  should  not  be  loaded  on  the  wagons 
and  should  be  burned  when  dry.'  Animals  should  not  be  put  on  pas- 
tures containing  an  abundance  of  arrow-grass  when  they  are  very 
hungry.  In  some  cases,  moreover,  portions  of  pastures  and  meadows 
where  arrow-grass  grows  in  great  abundance  should  be  fenced  and  left 
unused.  By  these  methods  it  should  be  easy  to  prevent  losses  due  to 
this  poisonous  plant. 


22 


PUBLICATIONS 


The  following  bulletins  are  available  for  distribution  and  may  be 
had  free  by  applying  to  the  Director  of  the  Agricultural  Experiment 
Station,  Reno,  Nevada : 

No.  Title 

31 Texas  Cattle  Fever. 

32 Sugar-Beets. 

52 Water  Supply  and  Irrigation  in  Nevada. 

TO Food  and  Drug  Inspection. 

71 Digestion  Experiments  on  the  Range. 

73 A  Neglected  Field  in  Photomicrography. 

74 Report  of  Department  of  Food  and  Drug  Inspection,  1910. 

76 ..The  Potato  Eelworm. 

77 Fixing  Standard  Weights  and  Measures. 

78 Hymenopterous  Parasites  (Technical)  Entomology. 

79 Avoidance  and  Prevention  of  Frosts  in  Fruit  Belts  of  Nevada. 

80 Food  and  Drugs  and  Weights  and  Measures  Laws  in  Nevada. 

81 Water  Hemlock  (Technical). 

83 Value  of  High-Level  Meteorological  Data  in  Forecasting  Changes  in 

Temperature. 

84 The  Control  of  Contagious  Epithelioma  in  Chickens  by  Vaccination. 

(Popular  Abstract  of  Bui.  82,  amplified  and  illustrated.) 

85 The  Use  of  Bacterins  in  the  Control  of  Fowl  Cholera. 

86 Forage  and  Root  Crops. 

89 Grain  Production  in  Nevada. 

90 Potato  Culture  in  Nevada. 

92 Irrigation  of  Wheat  in  Nevada. 

93 Irrigation  of  Alfalfa  in  Nevada. 

94 One-Night   Camps   vs.   Established   Bed-Grounds   on   Nevada    Sheep 

Ranges. 

96 Irrigation  of  Field  Crops  in  Nevada. 

97 Don't  Feed  Fox-Tail  Hay  to  Lambing  Ewes. 

98 Arrow-Grass,  a  New  Stock-Poisoning  Plant. 

Annual  Reports  for  1910,  1911,  1913,  1914,  1915,  1916,  1917,  1918. 
Circulars : 

1 Glanders. 

5 Inspection  of  Nursery  Stock. 

13 Anthrax. 


IN10N  (rfemj\BEE> 


Gaylord  Bros. 

Makers 

Syracuse,  N.  Y. 
PAT.  JAN.  21, 1908 


481270 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


